Armrest tilting device

ABSTRACT

A device for adjusting the inclination of the armrest by combined operation of the gear and cam mechanisms is provided. The device comprises a housing a ratchet member ( 12 ), a check member, a pivot control device comprising a fixed cam ( 22 ), a rotational com ( 24 ) and a torsion coil spring ( 32 ).

TECHNICAL FIELD

The present invention relates to an armrest tilting device, and moreparticularly, to an armrest tilting device wherein the gradient of therest bar may be adjusted by a step by step tilting operation of the restbar.

BACKGROUND ART

Armrests are generally used to rest an arm of an occupant of a seat or apassenger of an automobile. A conventional armrest for automobile seat,for example, is placed on an automobile seat so that an occupant can puther/his arm on it or positioned parallel with the back of the automobileseat by pivoting it upward when not in use.

Conventional armrests have a problem in that its inclination may not beadjusted, even if the occupant wants so for reading or taking acomfortable posture.

DISCLOSURE OF INVENTION

The present invention is made to solve the aforementioned problem.Accordingly, an object of the present invention is to provide an armresttilting device, made by combination of the gear and cam mechanismswherein the armrest can be tilted stepwise at predetermined angularintervals for the convenience of the occupant.

According to the present invention for achieving the above object andothers, there is provided an armrest tilting device, comprising ahousing comprising an outer panel with a supporting hole and an innerpanel with a passage hole, the two panels of which are coupled with agap therebetween and in parallel with each other; a ratchet member whichis arranged between the parallel panels and formed with a plurality ofteeth and a jaw; a check member comprising a pivotable gear formed witha jaw and teeth for engaging with the jaw and teeth of the ratchetmember and a torsion coil spring elastically supported on the pivotablegear, a rotational shaft which is rotatably supported in the supportinghole of the outer panel of the housing and passes through the passagehole of the inner panel of the housing, carrying either the ratchetmember or the pivotable gear and a rest bar of the armrest fixed on oneend thereof, and a pivoting control device arranged on the rotationalshaft outside the inner panel of the housing.

The pivoting control device is preferably comprised of a fixed cam,which is provided with a passage hole, one side of which is attached tothe inner panel of the housing so as for the two adjoining passage holesto be in alignment with each other, and the other side of which isformed with two recesses having a wall and a slant facing each other, arotational cam which is formed with two protrusions to be engagedrespectively with the recesses of the fixed cam and fixed on therotational shaft, a second torsion coil spring wounded around therotational shaft and arranged between the rotational cam and the otherend of the rotational shaft.

According to one aspect of the present invention, the ratchet member isfixed on the rotational shaft passing through its fixing hole, thepivotable gear is fixed between the outer and inner panels by means of apivot and the first torsion coil spring is hooked between the pivotablegear and the inner surface of one of the parallel panels.

According to another aspect of the present invention, the ratchet memberis fixed on the inner surface of one of the outer and inner panels, thepivotable gear is fixed on the rotational shaft via a support having amounting hole in which the shaft is fixed and the first torsion coilspring is hooked between the pivotable gear and the support for thepivotable gear.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an armrest tilting device accordingto an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the armrest tilting device ofFIG. 1;

FIGS. 3 a to 3 c are perspective views illustrating the operation of thearmrest tilting device of FIG. 1;

FIGS. 4 a to 4 e are sectional views illustrating the operation of thearmrest tilting device of FIG. 1;

FIG. 5 is a perspective view showing an armrest tilting device accordingto another embodiment of the present invention;

FIG. 6 is an exploded perspective view of the armrest tilting device ofFIG. 5;

FIGS. 7 a to 7 d are sectional views showing the operation of thearmrest tilting device of FIG. 5; and

FIG. 8 is a perspective view of a seat equipped with the armrest tiltingdevices of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.

EMBODIMENT 1

As shown in FIGS. 1 and 2, an armrest tilting device according to thefirst embodiment of the present invention comprises a housing comprisingan outer panel 10 with a supporting hole 10 a and an inner panel 10′with a passage hole 10 a′ the two panels of which are coupled with a gaptherebetween and in parallel with each other, a ratchet member 12interposed between the outer and inner panels 10, 10′ and formed with asupporting hole 12 a, a plurality of teeth 12 c and two jaws 12 b, 12 ca check member comprising a pivotable gear 14 with teeth 14 a forengaging with the teeth 12 a of the ratchet member 12 and a jaw 14 b anda first torsion coil spring 16 interposed between the inner surface ofthe inner panel 10′ of the housing, a rotational shaft 20 which isrotatably supported in the supporting hole of the outer panel 10 of thehousing and passes through the passage hole 10′a of the inner panel 10′of the housing, carrying a rest bar 18 of the armrest fixed on one endthereof and the ratchet member 12 fixed thereon with its mounting hole12 a and a pivoting control device comprising a fixed cam 22, arotational cam 24 and a second torsion coil spring 32 and arranged onthe rotational shaft 20 opposite the inner panel 10′ of the housing.

The outer and inner panels 10, 10′ are formed with a supporting hole 10a and a passage hole 10 a′ and four fastening holes 10 b at the cornersrespectively and arranged apart by a certain gap to seat the ratchetmember 12 and the pivotable gear 14 therein by means of fixing means(rivets, bolts or the like) inserted and fixed in the respectivefastening holes 10 b, while a hanging hole 10 c is provided on the innersurface of the outer panel 10 so that the other end of the first torsioncoil spring 16 is hooked therein.

The supporting hole 10 a of the outer panel 10 of the housing may have aball bearing or the like to support the rotational shaft 20.

The rivets fixed in the holes 10 b at the lower and upper ends of theouter and inner panels 10, 10′ in the vicinity of the ratchet member 12and the pivotable gear 14 have the function as a stopper 28, 30 forpreventing the excessive pivoting of the ratchet member 12 and thepivotable gear 14, respectively.

The ratchet member 12 is formed with an elliptical fixing hole 12 a tofixedly receive the rotational shaft 18 therethrough, while theplurality of teeth 12 c travel and engage with teeth 14 a of thepivotable gear 14.

The pivotable gear 14 is formed with a hole 14 b for receiving a pivot26 so that the pivotable gear 14 can be pivotably arranged between theouter and inner panels 10, 10′. The pivotable gear 14 is provided withteeth 14 a for engaging with teeth 12 c of the ratchet member 12, and ajaw 14 c.

The first torsion coil spring 16 has the shape of an open ring andresiliently supports the pivotable gear 14 against the ratchet member 12so that the teeth 12 a and 14 a of the ratchet member 12 and thepivotable gear 14 may be engaged with and disengaged from each other.

The first torsion coil spring 16 is disposed between the outer panel 10and the pivotable gear 14 and both ends of the spring 16 are hooked inthe hanging holes on the panel 10 and the pivotable gear 14. An end ofthe first torsion coil spring 16 may, of course, be hooked on the innerpanel 10′ instead of the outer panel 10.

The rotational shaft 20 in the shape of a rod is provided with a screwhole 20 a at its both ends and rotatably and rigidly held in the twosupporting holes 10 a and 24 b of the outer panel 10 and the rotationalcam 24.

One end of the rest bar 18 which adjoins the outer panel 10 is formedwith an elliptical fixing hole 18 a and fixed on one end of therotational shaft 20 by means of a bolt 36 inserted in the screw hole 20a, while the other part of the rest bar 18 is used as a handle forpivoting the armrest. The rest bar 18 is preferably covered with a softmaterial as the material of the seat.

In the pivoting control device, which also serves to prevent the restbar 18 from rocking during the tilting operation of the armrest, thefixed cam 22 attached to the inner panel 10′ is provided with a passagehole 22 d for the rotational shaft 20 as well as a vertical surface 22 band a step 22 c on its outer protruded circumference at its outer camportion.

The opposite two protrusions 24 a of the rotational cam 24 have aprecipice or wall and a slant so that they may engage with thecorresponding recesses 22 a of the fixed cam 22, while the rotationalcam 24 is fixed on the rotational shaft 20 by means of a supporting hole24 b receiving the shaft 20 therein.

The second torsion coil spring 32 is wound around the rotational shaft20 and disposed between the rotational cam 24 and a washer 34 fixed onthe other end of the shaft 20 by a bolt 36′ to urge the rotational cam24 toward the fixed cam 22.

The armrest to which the present invention is applied may be mounted onthe seat as shown in FIG. 8

Now, the operation of the armrest tilting device of the first embodimentof the present invention will be described.

When the armrest is placed parallel with the seat, teeth 14 a of thepivotable gear 14 engage with the front part of the teeth 12 a of theratchet member 12, while the fixed cam 22 and the rotational cam 24 fitwith each other with the protrusions 24 a of the rotational cam 24received in the recesses 22 a of the fixed cam 22 (see FIG. 4 a).

When the rest bar 18 is pulled upwardly, the rotational shaft 20 and theratchet member 12 are simultaneously rotated counterclockwise as can beseen from FIG. 4 b.

The teeth 14 a of the pivotable gear 14 travel and engage with rearteeth 12 a of the ratchet member 12 stepwise, making the rest bar 18 tobe tilted stepwise (four times in FIG. 4 b) upwardly. The slants of theprotrusions 24 a of the rotational cam 24 slide on or climb thecorresponding slant of the recesses 22 a of the fixed cam 24, making thesecond torsion coil spring 32 to be compressed (see FIG. 4 b).

The teeth of the ratchet member 12 and the pivotable gear 14 of thisembodiment are desirably designed so that the rest bar 18 and thearmrest as a whole may be tilted stepwise upwardly by 10 degrees throughone step, i.e. 40 degrees by four steps.

When teeth 14 a of the pivotable gear 14 meet and engage with the jaw 12b of the ratchet member 12, the latter thrust the former forward, makingthe pivotable gear 14 to be pivoted clockwise and disengaged from theratchet member 12. The pivotable gear 14 is then maintained in thepivoted position under the influence of the first torsion coil spring16.

The further clockwise pivoting of the pivotable gear 14 is checked bythe stopper 30. In this state, the fixed cam 22 and the rotational cam24 are in contact with each other as shown in FIG. 4 c.

Thereafter, the ratchet member 12 and also the rest bar 18 are rotatedwithout being checked by the check member of the pivotable gear 14 andthe first torsion coil spring 16 until it comes to meet the stopper 28(see FIG. 4 d).

In this state, the rest bar 18 is further pivoted upwardly and thus thetop surfaces of the protrusions 24 a of the rotational cam 24 slide onthe corresponding top surface of the fixed cam 22 until they are placedon the corresponding step 22 c formed thereon, as shown in FIG. 4 d andpivoting of the rest bar 18 is stopped as it reaches a position inparallel with the back of the seat. The free downward pivoting of therest bar 18 is checked, as the top surface the rotational cam 24 ispressed against the step 22 c of the fixed cam 22 by the second torsioncoil spring 32.

When the rest bar 18 is to be returned to a position for the occupant'suse, the top surfaces of protrusions 24 a of the rotational cam 24 mustcross over the vertical surface 22 b of the respective step 22 c and theforce for starting the pivoting motion of the rest bar 18 should bebigger than that of the second torsion coil spring 26 pressing the topsurfaces of the protrusions 24 a of the rotational cam 24 against thetop surfaces of the fixed cam 22.

After the top surfaces of the protrusions 24 a of the rotational cam 24have crossed over the vertical surface 22 b of the corresponding step 22c of the fixed cam 22, they are forced to slide on the rest portion ofthe top surface of the fixed cam 22 and the protrusions 24 a of therotational cam 24 go readily into the recesses 22 a of the fixed cam 22and the ratchet member 22 is pivoted clockwise as can be seen from FIG.4 e.

As the rotation of the fixed cam 22 is continued and its jaw 12 b comesto meet the jaw 14 c of the pivotable gear 14, the former pushes thelatter backward, making the pivotable gear 14 to be pivotedcounterclockwise so that its teeth 14 c may engage with the front partof the teeth 12 a of the ratchet member 12 as shown in FIG. 4 a.

EMBODIMENT 2

FIGS. 5 and 6 show an armrest tilting device according to the secondembodiment of the present invention, In this embodiment, the structureof the armrest tilting device is the same as that of the previousembodiment, except that a ratchet member 12′ having a plurality of teeth12′c and two opposite jaws 12′b, 12′c is fixed between the outer andinner panels 10, 10′ of the housing, a support 40 mounted on therotational shaft 20 and pivotably holding the pivotable gear 14′ havingteeth 14′a and opposite jaws 14′a, 14′b and the first torsion coilspring 16 is resiliently supported between the support 40 and thepivotable gear 14′.

In FIGS. 5 and 6, the same elements as those of the first embodiment arerepresented by the same reference numerals and symbols while thedescriptions for the same elements as those of the first embodimentapply to the second embodiment as well.

Now, the operation of the armrest tilting device of the secondembodiment of the present invention will be described.

When the armrest is placed parallel with the seat, teeth 14′a of thepivotable gear 14′, which is pivotably mounted on the support 40, engagewith the front part of the teeth 12′c of the ratchet member 12′, whilethe fixed cam 22 and the rotational cam 24 fit with each other with theprotrusions 24 a of the rotational cam 24 received in the recesses 22 aof the fixed cam 22 (see FIG. 7 a), in the same way as shown in FIG. 4a.

When the rest bar 18 is pulled upwardly, the rotational shaft 20 and thepivotable gear 14′ are simultaneously rotated counterclockwise as can beseen from FIG. 7 b.

The teeth 14′a of the pivotable gear 14′ travel and engage with rearteeth 12′c of the ratchet member 12′ stepwise, making the rest bar 18 tobe tilted stepwise (five times in FIG. 7 b) upwardly. The slants of theprotrusions 24 a of the rotational cam 24 slide on or climb thecorresponding slant of the recesses 22 a of the fixed cam 22, making thesecond torsion coil spring 32 to be compressed (see FIG. 7 b), in thesame way as shown in FIG. 4 b.

The teeth of the ratchet member 12′ and the pivotable gear 14′ of thisembodiment are desirably designed so that the rest bar 18 and thearmrest as a whole may be tilted stepwise upwardly by 10 degrees throughone step, i.e. 50 degrees by five steps.

When the jaw 14′b of the pivotable gear 14′ meet and engage with the jaw12′a of the ratchet member 12′, the latter prevent the former fromtraveling further, making the pivotable gear 14′ to be pivoted clockwiseand disengaged from the ratchet member 12′. The pivotable gear 14′ isthen maintained in the pivoted position under the influence of the firsttorsion coil spring 16 (see FIG. 7 c).

Thereafter, the pivotable gear 14′ and also the rest bar 18 are rotatedwithout being checked by any other elements until the support 40 for thepivotable gear comes to meet the stopper 28 (see FIG. 7 d).

In this sate, the pivot control device is operated in the same way asthat of the first embodiment, as shown in FIGS. 4 d and 4 e.

As the rotation of the pivotable gear 14′ is continued and its jaw 14′ccomes to meet the jaw 12′b of the ratchet member 12′, the former ispushed back and pivoted counterclockwise so that its teeth 14′a mayagain engage with the front part of the teeth 12′c of the ratchet member12′ as shown in FIG. 7 a.

It will be understood by those of ordinary skill in the art that any oneof the embodiments herein described and illustrated may be modified orrevised within the scope of the teachings of the present invention.

The present invention is not limited to the specific embodiments hereinshown and described but departures may be made therefrom within thescope of the accompanying claims without departing from the principlesof the invention.

INDUSTRIAL APPLICABILITY

As described above the present invention has an advantage in that atilting angle of an armrest can be adjusted at predetermined angularintervals for the convenience of an occupant.

1. An armrest tilting device, comprising; a housing comprising an outerpanel with a supporting hole and an inner panel with a passage hole, thetwo panels of which are coupled with a gap therebetween and in parallelwith each other; a ratchet member formed with a plurality of teeth and ajaw and arranged between said panels; a check member comprising apivotable gear formed with a jaw and teeth for engaging with the jaw andthe teeth of said ratchet member and a first torsion coil spring, forresiliently supporting said pivotable gear; a rotational shaft which isrotatably supported in the supporting hole of the outer panel of thehousing and passes through the passage hole of the inner panel of thehousing, carrying either the ratchet member or the pivotable gear and arest bar of the armrest fixed on one end thereof; a pivoting controldevice comprising a fixed cam having a passage hole for receiving saidrotational shaft therethrough , one side of which is attached to theoutside of the inner panel of said housing and the other side of whichis formed with two opposite recesses having a wall and a slant facingeach other, a rotational cam fixedly mounted on said rotational shaft,one side of which faces the recesses of said fixed cam and is formedwith two opposite protrusions having a wall and a slant for beingengaged with the corresponding recesses of said fixed cam, and a secondtorsion coil spring wound around said rotational shaft and arranged andsupported between said rotational cam and the other end of saidrotational shaft for pressing said rotational cam against said fixedcam.
 2. The armrest tilting device as claimed in claim 1, wherein saidrotational shaft carries said ratchet member fixed thereon by a mountinghole of said ratchet member, said pivotable gear is pivotably mountedbetween said panels and said first torsion coil spring is hooked betweensaid pivotable gear and either of said panels.
 3. The armrest tiltingdevice as claimed in claim 2, wherein a lower step is formed on a partof each top surface of the cam portion of said fixed cam so that the topsurfaces of the protrusions of said rotational cam may be seated thereonand the protrusions of said rotational cam may be locked by theadjoining vertical surface of said step.
 4. The armrest tilting deviceas claimed in claim 3, wherein a stopper for checking excessive pivotalmovement of either or both of said ratchet member and said pivotablegear is provided by fixing means coupling said panels.
 5. The armresttilting device as claimed in claim 4, wherein said fixing means is arivet.
 6. The armrest tilting device as claimed in claim 2, wherein astopper for checking excessive pivotal movement of either or both ofsaid ratchet member and said pivotable gear is provided by fixing meanscoupling said panels.
 7. The armrest tilting device as claimed in claim6, wherein said fixing means is a rivet.
 8. The armrest tilting deviceas claimed in claim 1, wherein said rotational shaft carries saidpivotable gear by a support for said pivotable gear which is mountedthereon and to which said pivotable gear is pivotably fixed, saidratchet member is fixed on the inside of either or both of said panels,and said first torsion coil spring is hooked between said pivotable gearand said support for said pivotable gear.
 9. The armrest tilting deviceas claimed in claim 8, wherein a lower step is formed on a part of eachtop surface of the cam portion of said fixed cam so that the topsurfaces of the protrusions of said rotational cam may be seated thereonand the protrusions of said rotational cam may be locked by theadjoining vertical surface of said step.
 10. The armrest tilting deviceas claimed in claim 9, wherein a stopper for checking excessive pivotalmovement of either or both of said ratchet member and said pivotablegear is provided by fixing means coupling said panels.
 11. The armresttilting device as claimed in claim 10, wherein said fixing means is arivet.
 12. The armrest tilting device as claimed in claim 8, wherein astopper for checking excessive pivotal movement of either or both ofsaid ratchet member and said pivotable gear is provided by fixing meanscoupling said panels.
 13. The armrest tilting device as claimed in claim12, wherein said fixing means is a rivet.
 14. The armrest tilting deviceas claimed in claim 1, wherein a lower step is formed on a part of eachtop surface of the cam portion of said fixed cam so that the topsurfaces of the protrusions of said rotational cam may be seated thereonand the protrusions of said rotational cam may be locked by theadjoining vertical surface of said step.
 15. The armrest tilting deviceas claimed in claim 14, wherein a stopper for checking excessive pivotalmovement of either or both of said ratchet member and said pivotablegear is provided by fixing means coupling said panels.
 16. The armresttilting device as claimed in claim 15, wherein said fixing means is arivet.
 17. The armrest tilting device as claimed in claim 1 wherein, astopper for checking excessive pivotal movement of either or both ofsaid ratchet member and said pivotable gear is provided by a fixingmeans coupling said panels.
 18. The armrest tilting device as claimed inclaim 17, wherein said fixing means is a rivet.